Telephone-receiver



(No M0de1,) 2 Sheets-Sheet l.

W. H. COLLINS. TELEPHONE EEGEIVEE.

Nm 381,531x PatentedApr. 24, 1888.

2 Sheets- Sheet 2.

(No ModeL).

W.y H. COLLINS.

TELEPHONE RECEIVER.

Patented Apr. 24, 1888.

Wijf/63365,

n w r .0 o u a 0 mw .w

UNTTED STATES PATENT Ormea.

WILLIAM H. COLLINS, OF CHICAGO, ILLINOIS, ASSIGNOB OF ONE-HALF TO JACOB KIRKNER, OF NEW YORK, N. Y., AND ROBERT BINES, OF CHICAGO,

ILLINOIS.

TELEPHONEeRECEIVER.

SPECIFICATION forming part of Letters Patent No. 381,531, eaten April ze, 188e.

Application filed March 11, 1887. Serial No. 230,560. (No model.)

To @ZZ whom. if; may concern:

Be it known that I, XVILLIAM H. CoLLINs, a citizen of the United States, residing at Chicago, in the county of Cool; and State of Illinois, have invented a certain new and useful Improvement in Telephone-Receivers, which is fully set forth in the following specification, reference being had to the accompanying drawings, in which- Figure lis a front elevation of an apparatus embodying my invention in one form; Fig. 2, a sectional view of the same,taken on the line .o of Fig. I; Fig. 3, a sectional vieu7 taken on the line y y of Fig. 2; Fig. 4, a detail front face View of the magnets and coils detached; Fig. 5, a front face view or elevation of a modified forni of apparatus, the diaphragm being removed; Fig. 6, a rear View of the same with the back of the cup or casing removed; Fig. 7, a sectional View taken on theline e' z of Fig. 5; Fig. 8, a det-ail View of the magnets and coils detached; Fig. 9, a view similar to Fig. 5 of another`modiiied form of apparatus; Fig. 10, a vieur similar to Fig. 8 of another modiiication, and Fig. ll a view similar to Fig. 8 of another modication.

Like letters refer to like parts in all the gures of the drawings.

My invention relates to telephone receivers, or, in other words, to sound-reproducing de Vices employed in conjunction with a suitable transmittenwhereby sound is transmitted by means of electricity. It has for its object to produce a receiver of increased effectiveness in operation; and to these ends my invention consists in certain novel features,which I will nonT proceed to describe, and will then particularly point out in the claims.

In the drawings, A represents a suitable cup or casing, constructed of glass, hard rub ber, or any other good sound-insulating material, and forming the outer casing of the instrument. This cup is preferably secured Within the telephone B, its outer margin he-v ing screw-threaded to screw into a correspondinglyihreadcd retaining-ring, A, lattaclied to the inside of the said box B in any suitable manner. Between the meeting edges of the cup or casing A and the retaining-ring A a suitable seat is formed to receive the dia phragm C, which is thus held firmly by its margin between the ring and casing. The box B is cut away in front of the diaphragm, as shown at b, to form an aperture for the pas sage of the sound-Waves 'from the diaphragm to the exterior of the box, and a ring, d, is provided on the outer side of the box B, surround ing the aperture b, for the attachment of a ilexilole tube, D, for conveying the sound to the ear, said tube being provided With a suitablyshaped ear-piece, D', for the purpose.

Vithin the cup or casing A, at the rear thereof, is secured a soft-iron plate or bar, E, upon which is mounted centrally a soft-iron core, F, preferably constructed of iinc iron Wires; but it may of course be constructed in a single piece, although I prefer the construction shown. A disk, e, of Wood, rubber, or other insulating material, surrounds the core F at its rear end, and represents one end or head of the spool of the induction-coil surrounding the core F.

G represents a coil of the primary Wire, prefa erably a copper Wire, which is covered with any suitable insulating material, so as to insu- 7 5 late it from the core and secondary coil, and is connected at one end by a portion, g, thereof to a binding-post, G', from which a. Wire leads to the battery. This primary coil Gr is surrounded by a secondary coil, H, of fine copper wire, the ends of which are led to bindingposts k, suitably connected to the line upon which the transmitter is located. The second' ary coil extends, along with the primary coil and core F, almost tothe diaphragm, there being no spool-head at the front end, so that the end surface of the said secondary coil is exposed to the diaphragm as Well as the core.

I represents a soft-iron cylinder mounted on the plate E and surrounding the core F and its coils G and H, but not in contact with them. This cylinder extends forward to an extent equal to the length of the core F and its coils, their front surfaces being all on a level and a short distance in the rear of the diaphragm. The primary wire is Wound around this cylinder to form a coil, G2, which is preferably so connected with the coil G as to give to the cyl inder I a polarity the reverse of the core F, the connecting portion g of the primary wire being connected to the inner portion of the coil G2 and to the outer portion of the coil G. From the coil G2 the primary wire is led by a portion, g2, to a second binding-post, G3, from which a wire leads to the other pole of the bat-- tery.

Instead of so connecting the auxiliary core formed by the cylinder I as to give it a polarity the reverse of that of the central core, F, it may have the same polarity; but I prefer the yconstruction and arrangement shown. Moreover, instead of arranging this auxiliary core in the form of a cylinder surrounding the central core and its coils, it may be arranged at one side thereof, as shown in Figs. 5 to 8, inclusive, of the drawings, in which the aux-y iliary core I and its coils G2 of primary wire are shown as mounted upon one end of the plate E and the main core and its coils mounted on the other end. In order to obtain a central position, which I deem preferable, although by no means indispensable, for the main core, I may adopt the construction shown in Fig. 9, in which the main core is opposite the center of the diaphragm,while two of the cores I are employed, one on each side thereof. This is, however, a mere duplication of the second core, the principle being identical, and it is obvious that a series of these cores suitably arranged may be employed in conjunction with the main core; or, indeed, they may be entirely dispensed with, (see Fig. 11,) relying entirely upon the action of the main core and its coil upon the diaphragm, although I prefer to employ these auxiliary cores in one form or another.

The operation of the instrument is as follows: A current passing through the primary wire and its coils from the battery magnetizes the cores F and G2 and the diaphragm C, which is in the magnetic field. The exposed end surface of the secondary coil likewise iniiuences the diaphragm when any electrical` disturbances of the battery-current occur. Any electric current received from the main-line wire, due tothe transmitter thereon located, will pass through the secondary coil, and will thereby affect the current passing through the primary coils, increasing or diminishing thesame, as the case may be, and causing an increase or diminution in the action of the cores upon the diaphragm, thereby imparting to the same a vibratory action corresponding to that of the transmittinginstrument, and causing it to reproduce the sounds which cause the original vibrations. The secondary coil also partakes of this increase and decrease in its magnetic action, and operates upon the diaphragm in conjunction with the main core or magnet, its end surface heilig exposed, as hereinbefore described, so that a magnetic field of increased intensity is thereby produced, and the action of the diaphragm is thus-rendered more ample and efficient.

In the construction just described the secondary lcoil H is connected to the line, Yand serves not only to increase the intensity of the magnetic field, as just pointed out, but also to val-'y the battery-current, as stated in the preceding paragraph. Now this latter function may be performed by means of a separate coil, and in Fig. I0 of the drawings I have shown a construction embodying this modification. In this case the coil H is not connected to the line, but has its ends connected to each other, while a separate secondary coil, H', surrounding one of the coils of primary wire on one of the auxiliary cores, is connected to the line. In this construction the line-eurrent, passing through the coil H', will vary the battery-current by its action upon that coil of primary wire which is surrounded by the said second` ary coil H. The battery-current thus varied will of course act upon the coil H through the medium of the coil G inclosed thereby, and a current corresponding to the line-current will Ythus be created in the said secondary coil H.

The magneticeiiect of the main core F and exposed coil H upon the diaphragm will thus be substantially the same las in the construction hereinbefore described.

It is obvious that various moditicatio'ns may be made without departing from the principle of my invention. For instance, instead of mounting the receiver in a xed position Within the box and employing a iiexible tube to convey the sound to the ear, the cup or casing may be detached and connected to the transmitter in the usual manner, but with a three or four strand cord. Moreover, various otherI IOO IIO

IIS

ing said primary coil, connected to the line,

and having its end surface exposed to the diaphragm and exerting a magnetic influence thereon, substantially as and for the purposes specified.

2. In a telephone-receiver, the combination, with a vibratory diaphragm of magnetic material, of a soft-iron core, a coil of primary wire surrounding said core and suitably connected to a battery or other source of electricity, and a coil of secondary wire surrounding said primary coil and suitably connected to the line, the said coils having their end surfaces exposed to the diaphragm and exerting a magnetic iniiuence thereon, substantially as and for the purposes specified.

3. In a telephone-receiver, the combination, with the vibratory diaphragm of magnetic maprimary wire surrounding the same and connected to a battery or other source of eleotrioity, a coil of Secondary Wire surroundlng said primary coil and connected to the line, the cylindrical auxiliary soft-iron core surrounding the said core and coils and itself surrounded by a coil of the primary Wire, and au iron plate on which both cores are mounted, Substantially as and for the purposes specified.

WILLIAM H. COLLINS. Vitnesses:

IRVINE MILLER, ORSON H. BROOKE, 

